Control system



Aug, 30, 1927.

. 1,640,559 E. M. BOUTON common syswml Filed April 12. 1921 WITNESSES: INVENTOR fdydf'Mfiollmfl- BY -V ."ATTORNEY Patented Aug. 30, 1927.

UNITED A STATES PATENT OFFICE.

EDGAR M. BOUTON, OF EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING- HOT'SE ELECTRIC &; MANUFACTURING COMPANY, CORPORATION OF PENNSYL- VANIA.

.. CONTROL SYSTEM.

Application filed April 12, 1921. Serial in. 460,844.

My invention relates to motor-control systems and it has particular relation to such systems of control as are employed with elevators, dumb-waiters and the like.

The object of my invention is to provide a system of control whereby an elevator may be automatically dispatched to any desired landing or floor and in which no regular operator is resquired.

Systems of such character have come into general use, but, in the main, are perhaps unnecessarily complicatedr I propose to provide a standard elevator hoisting mechanism with a suitable reversing controller operated by means of pushbutton switches located as desired or convenient. A. plurality of selector switches are located, one at each-landing, and arranged for operation by the movement of the elevator car. Relays coact with the push-button switches and selector switches to control the movement of the elevator whereby it may be called to any desired landing and dispatched therefrom to any other landing.

I have shown a single figure which represents, diagrammatically, circuits and apparatus embodying my invention.

A motor, having an armature 1 and a shunt field 1a, is connected to line conductors 2 and 3 by means of reversing contactors 4 and 5. An accelerating resistor 6 is controlled by a contactor 7, and a dynamicbraking resistor 8 is controlled, in the usual manner, by the reversing contacto'rs. An electro-mechanical brake 9 is provided to hold the elevator car at any desired point in its travel. The operation of this brake is controlled by means of a relay 11.

Relays 12 and 13, together with reversing contactors 4 and 5, are responsive to the operation of push-button switches of a plurality of similar groups 14. Selector switches 15, 16, 17 and 18 are actuated by the cam 19' attached to the elevator car 21. Door switches 22, 23, 24 and 25 control the movements of the eley ator in a well known manner; the elevator is inoperative when any door switch is open.

Assuming the elevator car is at the third floor, corresponding to the location of selector switch 17 and door switch 24, if it is de-' sired to dispatch the elevator to the first floor, push-button switch 26 is de ressed momentarily, establishing a circuit or the I coil 27 of contactor 5, extending from line conductor 2 through conductors 28 and 29,

back contact 31 of relay 11, conductors 32 and 33, push-button switch 26, conductors 34 and 35, selector switch 15, conductor 36, coil 27, conductor 37 and door switches 25,

I 24, 23 and 22 to line conductor 3. The closure of contactor 5 establishes a circuit for the operating coil 38 of rela .11- extending from line conductor 2 throug conductor 39, contactor 5, conductor 41, holding coil 42, braking contactor, 43, a section of resistor 8, conductor 44 and coil 38 to line conduc-. tor 3.

The closure of relay 11 interrupts a circuit through the push-button through the back contact 31. A holding circuit has previously been established for the coil 27 of contactor 5, extending from line conductor 2 through conductor 39, contactor 5, conductor 41, coil 42, contact 43, resistor 8, conductor 44, back contacts 45 and 46 of relays 13 and 12, resistor 47, conductors 34 and 35, selector switch '15, conductor 36, coil 27, conductor 37 and door switches 25, 24, 23 and 22 to line conductor 3.

The elevator is directed to the first floor and, in passing the second floor, may actuate selector switch 16. It will be noted, however, that the circuits previously traced do not comprise selector switch 16. There- 86 fore, the elevator continues to operate until the selector switch 15 is actuated, interrupting .the holding circuit previously traced, comprising coil 27 and contactor 5. The elevatoris, therefore, quickly brought 90 to rest in the usual manner.

Assuming it was desired to dispatch the elevator to the second floor from the third, instead of to the first, as described, it is necessary to momentarily depress pushbutton 48, establishing a circuit for coil 49 of relay 12 and coil 27 of contactor 5, extending from line conductor 2 through conductors 28 and 29, contact '31, conductors 32, 33 and 50, push-button switch 48, con 1 duotor 51, coil 49, conductor 52, selector switch 16, conductor 53, selector switch 15, conductor 36, coil 27, conductor 37 and door switches 25, 24, 23 and 22 to line conductor switches 7 3. A holding circuit for contactor 5 and rela 12 is established, extending from line con ,uctor 2 through conductor 39, contactor .5, conductor 41, coil 42, contact 43, resistor .8, conductor 44, contact 45, relay 12, C011 49, conductor 52, selector switch 16, conductor 53, selector switch 15, conductor 36, c011 27, conductor 37 and door switches 25, 24, 23 and 22 to line conductor 3. Relay 11 lnterrupts the initial operating circuit through all of the push-button switches, as previously described.

The elevator car 21 is directed to the second floor and is stopped at that floor b the actuation of selector switch 16, whic interrupts the circuit previously described for relay 12 and contactor 5. \Vh1le relay 12 is closed, a circuit for servlng the first floor is interrupted through back contact 46, which circuit comprises resistor 47,- selector switch 15 and operating coil 27 of contactor 5. It is also assumed that door switch 23 is opened automatically, in any well known manner, by the elevator car 21 or by a passenger in the car, so that, while the door at the second landing is open, the elevator cannot be dispatched to or called from any other landing.

If it is desired to dispatch the elevator car to the fourth landing, circuits are establishedv comprising an operating circuit for the coil 55 of the contactor 4, extending from line conductor 2 through conductors 28 and 29, contact 31, conductors 32 and 33, push-button switch 56, conductor 57, selector switch 18, conductor 58, coil 55, conductor 37 and door switches 25, 24, 23 and 22 to line conductor 3. A holdin circuit for the coil 55 is established, exten ing from line conductor 2 through contactor 4, conductor 59, coil 61, back contact 62, resistor 8, conductor 44, contacts 45 and 46, resistor 63, conductor 57, selector switch 18, conductor 58, coil 55, conductor 37 and door switches 25, 24, 23 and 22 to line conductor 3. The operation of the elevator in its upward movement to the fourth floor is similar to that described in its movement to the first floor.

It should be noted that resistors 47 and 63 are of such value as to prevent accidental operation of contactors 4 and 5 by limiting the current to a value below the value necessary to operate these contactors, while permitting sufiicient current to flow to maintain these contactors closed after they have been operated in the proper manner. Also, relay 13 functions with respect to selector switch 17 in a manner similar to that in which'relay 12 and selector switch 16 coact. When relay 13 has functioned to serve the third floor, all other operatin circuits are interrupted by the opening of back contact 45.

Any number of floors may be served by the addition of a corresponding number of selector switches, push-button switches door switches and relays corresponding in operation to relay 12. If deslred, a oup of push-button switches may be locate at each floor, as is convenient for the control of a dumb-waiter, since it is not designed to carry passengers. In elevator service one group is located within the elevator car under control of the passengers and other buttons are distributed, one at each of the corresponding floors, to call the car to that floor, after which the car is dispatched to any desired floor by means of the buttons located in the car.

In systems commonly employed, a selector device is connected to the elevator mechanism by means of a chain or gearing. With this arrangement, it is necessary to readjust the selector device from time to time on account of stretching of the elevator hoisting cables, which eventually take a permanent set. The point at which the elevator stops and the relation of the landing level and car fioor'level also varies in accordance with the load in the car on account of the elasticity of the hoisting cables. In the present system, this difiiculty is overcome by locating the selector switches at the floors where they are actuated directly by the elevator car.

The selector switch mechanism employed in this system is very simple in form, inexpensive in construction and requires a minimum of attention for maintenance. The common type of hatchway limit switch may be employed.

I have shown a simple form of o erative control system which is capable o modification to suit particular needs without departing from the essential features and scoIpe of my invention.

claim as my invention 1. The combination with an elevator and a hoisting motor, of reversing contactors therefor, controlling means comprising a plurality of push-button switches-and selector switches, a brake for the motor, a relay responsive to the operation of one of said reversing contactors in response to the op- (ration of one of said push button switches for controlling said brake, and a switch actuated by the brake rela for rendering all the other of said push uttons ineffective. 2. The combination with an elevator and a hoisting motor therefor, of a pair of contactors for reversing the motor, a holding circuit for said contactors a lurality of selector switches actuated by tile elevator and a plurality of push-button switches for actuating said contactors and for dispatching the elevator to either of two predetermined landings, selectively, a relay responsive to one only of said push-button switches, a selector switch coact-ing therewith for dispatching said elevator 'to a, predetermined intermediate landing, and mean comprising said relay for interrupting the holding circuit for said reversing contaetors comprising said reversing contactors and a pair of said selector switches.

3. The combination with an elevator and a hoisting motor therefor, of a pair of contactors for reversing the motor, a plurality of selector switches operated by the elevator, a plurality of push-button switches for actuating said contactors, electroresponsive means comprising only said contactors and a pair of said selector switches for determi'nmg the limits of travel of said elevator, and a relay responsive to the operation of another of said selector switches and to said push-button switches for accomplishing an intermediate predetermined stop for the elevator.

4. The combination with an elevator and a hoisting motor therefor, of a pair of reversing contactors having dynamic braking contactors attached thereto, a plurality of push-button switches for effecting the actuation of said reversing contactors, a holding circuit for the operating coil of one of said reversing contactors, comprising the braking c'ontactor of the other of said reversing contactors, and a plurality of selector switches actuated by said elevator for interrupting said holding circuit when said elevator occupies a predetermined osition.

In testimony whereof, I have hereunto V subscribed my name this 28th day of March,

EDGAR M. BOUTON. 

